Clean up unneeded owners

Remove owners for *android* files in ui/OWNERS since there are no such
files in that directory. Per-file rules aren't recursive.

BUG=309856
NOTRY=true

Review URL: https://codereview.chromium.org/34873002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230174 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230174